1. Field of the Invention
The present invention relates to flavor enhancers and, more particularly, to substantially salt-free protein hydrolyzate flavor enhancers and to methods of preparing the same.
2. Description of the Prior Art
Protein hydrolyzates are incorporated into foods to increase nitritional value and to enhance the flavor of the foods. Until now, the hydrolyzates have exhibited an undesirably high salt content as an unavoidable incident of the process by which they are prepared. the typical salt content of solid protein hydrolyzates available in the market varies from 45 to 55%, and in liquid hydrolyzates from 20 to 25%. While salt is useful in helping to prevent spoilage in the protein hydrolyzate, high levels are undesirable because the product cannot be used in salt-free diets.
It is well known to product sugar-based, protein hydrolyzate flavor enhancers by reaction of a reducing sugar with an amino acid component (such as hydrolyzed protein). However, the methods presently utilized in the art to produce the hydrolyzed protein amino acid component are incapable of providing salt-free or substantially salt-free products. Specifically, the generally used method of preparing amino acid containing hydrolyzed proteins for reaction with reducing sugars comprises hydrolyzing protein starting material with hydrochloric acid and neutralizing the hydrolyzed amino acids with sodium carbonate. Such a method typically yields hydrolyzates containing 45-55% salt. As a result, the sugar-based flavor enhancers made therefrom contain undesirably large quantities of salt.
U.S. Pat. No. 3,480,447 discloses a process for preparing a seasoning preparation whereby an amino acid component is reacted with one or more reducing sugars in the presence of a lower aminoalkanesulfonic acid or salt. U.S. Pat. No. 3,493,395 discloses reacting amino acids obtained from protein hydrolyzates with reducing sugars in the presence of an oil or fat. U.S. Pat. No. 2,934,437 teaches reacting cysteine or cystine with a pentose or hexose monosaccharide to produce an artificial flavoring. While each of these prior art processes produce sugar-based hydrolyzates, the hydrolyzates are all salt-rich seasonings unsuitable for use in salt-free diets. Moreover, these processes have been found to produce seasonings exhibiting less than optimum flavor due to uncontrolled side reactions in the reducing sugar/amino acid reaction mixtures.